Platform trailer with extruded floor panel cross members

ABSTRACT

A platform trailer includes first and second aluminum beams. The first and second beams are defined with an arch. A platform is supported on the first and second beams. The platform includes a plurality of extruded aluminum panels that each extend from a left lateral end abutted with the left side rail to a right lateral end abutted with the right side rail. The extruded aluminum panels are abutted in series with the first end wall of one panel abutted with the second end wall of an adjacent abutted panel such that the respective upper walls of adjacent abutted panels of the platform together define an upper, cargo supporting surface of the platform. The platform is arched to correspond with the arch of the first and second beams. A method for constructing the platform trailer is also disclosed.

This application claims priority from and benefit of the filing date ofU.S. provisional application Ser. No. 60/856,436 filed Nov. 3, 2006 andsaid provisional application Ser. No. 60/856,436 is hereby expresslyincorporated by reference into the present specification.

BACKGROUND

FIGS. 1A and 1B are left (driver side) and right (passenger side)elevational views, respectively, of a conventional semi-trailer Tadapted to be connected to and pulled by a conventional tractor/truck(not shown). The trailer T comprises a forward end FT and a rear end RTspaced-apart from each other on a longitudinal axis L. FIGS. 2A and 2Bare plan and cross section views of the trailer T as taken along viewlines A-A and B-B of FIG. 1A, respectively. Referring also to thesedrawings, it can be seen that the trailer T further comprises acargo-supporting platform P including left and right laterallyspaced-apart sides LP,RP. The platform P is supported by and connectedto a chassis C that includes first (left) and second (right)spaced-apart beams B1,B2 that extend parallel to each other and to thelongitudinal axis L from the forward end FT to the rear end RT. Eachbeam B1,B2 defines an I-beam profile comprising an upper flange F1 and alower flange F2 (FIG. 2B) connected by a web BW. The beams can be steelor aluminum and are often fabricated by welding or otherwise abuttingand welding together or otherwise connecting two separate T-shapedaluminum extrusions.

A kingpin K is located at the forward end FT of the trailer T, centrallylocated between and connected to the beams B1,B2, and is adapted to beengaged by a fifth-wheel of an associated tractor/truck for towing thetrailer T. The rear end RT of the trailer includes at least one andtypically at least two axle assemblies A connected to the chassis, e.g.,to the lower flanges F2 of beams B1,B2. Each axle assembly A comprisesat least one left and at least one right rotatable wheel and tireassemblies W for movably supporting the trailer T on a road or othersurface. The trailer T further comprises a dolly assembly D, typicallylocated axially between the kingpin K and an axial midpoint of thetrailer T. The dolly assembly D includes support feet DF that areselectively lowered to support the forward end FT of the trailer T whenthe kingpin is not connected to an associated tractor/truck (the dollyassembly D is omitted from the background of FIG. 2B for clarity).

The platform P comprises left and right side rails RL,RR that delimitthe opposite lateral sides LP,RP of the platform, respectively. Theseside rails RL,RR are each typically defined as one-piece or monolithicextrusions of aluminum alloy (often referred to herein simply as“aluminum”) having a profile such as that shown in FIG. 2B and thatextend in one piece from the forward end FT to the rear end RT of thetrailer T, and that lie in respective vertical planes that are parallelto the webs BW of beams B1,B2 and the longitudinal axis L (the profilesof the side rails RL,RR are typically mirror images of each other asshown herein). The side rails RL,RR are often arched as shown in FIGS.1A and 1B with an apex of the arch oriented upward and located betweenthe forward and rear ends FT,RT.

The platform P, itself, comprises left, middle and right sectionsPL,PM,PR that each comprise one or more wood and/or metal longitudinallyextending platform members PK, each of which extends longitudinally fromthe forward end FT to the rear end RT of the trailer T, as one-piece orotherwise to define an upper cargo-supporting surface P1. Typically, theplatform members PK comprise aluminum extrusions and/or wooden planks orthe like. Regardless of the material used to define the platform membersPK, it should be noted that they extend longitudinally between theforward and rear trailer ends FT,RT, but do not extend transverselybetween the left and right side rails RL,RR, i.e., each platform memberPK fills only a fraction of the space between the left and right siderails RL,RR. In the illustrated trailer embodiment, the upper flange F1of each beam B1,B2 also defines part of the platform P, with the upperflange F1 of the first (left) beam B1 connected to both of the left andmiddle platform sections PL,PM and the upper flange F1 of the second(right) beam B2 connected to both of the right and middle platformsections PR,PM.

In each of the left, middle, and right sections PL,PM,PR, the platformmembers PK extend in a longitudinal direction that is parallel to theaxis L and beams B1,B2, but platform members PK from each sectionPL,PM,PR do not extend transversely from one section PL,PM,PR to anothersection PL,PM,PR. If the beams B1,B2 and side rails RL,RR are arched,the platform members PK are correspondingly arched. As such, to supportthe longitudinally extending platform members PK, the platform P oftrailer T must further comprises a plurality of transversely extendingcross members CM located beneath the platform members PK at axiallyspaced intervals along the entire length of the trailer T. The crossmembers CM are welded or otherwise connected to and extend between theleft and right side rails RL,RR, passing through and typically welded tothe beams B1,B2 (in some cases the cross members CM comprise threeseparate sections cross member sections located respectively beneath andsupporting the left, middle and right platform sections PL,PM,PR insteadof a single member that passes through the beams B1,B2). These crossmembers CM can have a variety of shapes, e.g., I-beam, U-shaped,C-shaped, etc. and be defined from a variety of materials such as steelor aluminum, e.g., aluminum extrusions. The use of cross members CMincreases labor and material costs, and the cross-members create anuneven underside P2 to the platform P which increases wind drag and/orincludes locations for dirt, ice and other debris to accumulate betweenthe cross members.

SUMMARY

In accordance with one aspect of the present development, a platformtrailer includes a chassis comprising first and second aluminum beamseach including an upper flange and a lower flange connected by a web.The first and second beams are arranged parallel to each other and eachextend from a forward end to a rear end in the direction of alongitudinal axis of the trailer. The first and second beams are eachdefined with an arch comprising an upwardly oriented apex locatedbetween the forward and rear ends. At least one axle assembly connectedto the chassis and includes a left wheel and tire assembly and a rightwheel and tire assembly. A platform is supported on the first and secondbeams of the chassis. The platform includes spaced-apart left and rightside rails and a plurality of extruded aluminum panels that each extendfrom a left lateral end abutted with said left side rail to a rightlateral end abutted with said right side rail. Each of the panelscomprises an upper wall, a lower wall spaced-apart from the upper wall,and first and second spaced-apart end walls that are connected to andextend between the upper and lower walls. The extruded aluminum panelsare abutted in series with the first end wall of one panel abutted withthe second end wall of an adjacent abutted panel such that therespective upper walls of adjacent abutted panels of the platformtogether define an upper, cargo supporting surface of the platform. Theplatform is arched to correspond with the arch of the first and secondbeams.

In accordance with another aspect of the present development, a methodfor constructing a platform trailer includes constructing a platformsubassembly comprising plurality of extruded aluminum panels that eachextend from a left lateral end to a right lateral end. Each of thepanels includes an upper wall, a lower wall spaced-apart from the upperwall, and first and second spaced-apart end walls that are connected toand extend between the upper and lower walls. The extruded aluminumpanels are abutted in series with the first end wall of one panelabutted with the second end wall of an adjacent abutted panel such thatthe respective upper walls of adjacent abutted panels define an upper,cargo supporting surface of the platform subassembly. A force is exertedon the platform subassembly to form an arch in the platform subassembly.While the force is applied to maintain the arch in the platformsubassembly, first and second parallel, spaced apart arched beams arewelded to the platform subassembly. The force is then removed from theplatform subassembly after said first and second arched beams are weldedto the platform subassembly.

In accordance with another aspect of the present development, a methodfor constructing a platform trailer includes constructing a platformsubassembly comprising plurality of extruded aluminum panels that eachextend from a left lateral end to a right lateral end, each of saidpanels comprising an upper wall, a lower wall spaced-apart from saidupper wall, and first and second spaced-apart end walls that areconnected to and extend between the upper and lower walls. The extrudedaluminum panels are abutted in series with the first end wall of onepanel abutted with the second end wall of an adjacent abutted panel suchthat the respective upper walls of adjacent abutted panels define anupper, cargo supporting surface of said platform subassembly. Theconstructing step includes welding the adjacent abutted panels to eachother such that said platform subassembly defines a built-in arch. Firstand second parallel, spaced apart arched beams are then welded to saidplatform subassembly.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A and 1B are left (driver side) and right (passenger side)elevational views, respectively, of a conventional semi-trailer Tadapted to be connected to and pulled by a conventional tractor/truck(not shown).

FIGS. 2A and 2B are plan and cross section views of the trailer T astaken along view lines A-A and B-B of FIG. 1A, respectively.

FIGS. 3A and 3B are left (driver side) and right (passenger side)elevational views, respectively, of a semi-trailer T′ formed inaccordance with the present invention and adapted to be connected to andpulled by a conventional tractor/truck (not shown).

FIGS. 4A and 4B are plan and cross section views of the trailer T′ astaken along view lines A-A and B-B of FIG. 3A, respectively.

FIG. 4C is a sectional view of the platform P′ as taken at line C-C ofFIG. 4B, and shows first and second extruded floor panels XP (i.e.,first panel XP1 and second panel XP2) of the platform P′.

FIG. 5 illustrates the extrusion profile of an individual panel XPformed in accordance with the present invention.

FIG. 6 illustrates the extrusion profile of an alternative floor panelXP′ that is identical to the panel XP except as otherwise shown and/ordescribed.

FIG. 7 illustrates one method of manufacturing a trailer platformincluding an arch according to the present development.

FIGS. 8A and 8B illustrate another method of manufacturing a trailerplatform including an arch according to the present development.

FIGS. 9 and 10 illustrate alternative profiles for the beams B1,B2.

DETAILED DESCRIPTION

FIGS. 3A and 3B are left (driver side) and right (passenger side)elevational views, respectively, of a semi-trailer T′ formed inaccordance with the present invention and adapted to be connected to andpulled by a conventional tractor/truck (not shown). Except as otherwiseshown and/or described herein, the trailer T′ is identical to the priorart trailer T and, as such, like components of the trailer T′ relativeto the trailer T are identified using the same reference characters usedin the description of the trailer T, in some cases without repeating theabove descriptions. The trailer T′ comprises a forward end FT and a rearend RT spaced-apart from each other on a longitudinal axis L.

FIGS. 4A and 4B are plan and cross section views of the trailer T′ astaken along view lines A-A and B-B of FIG. 3A, respectively. Referringalso to these drawings, the trailer T′ further comprises acargo-supporting platform P′ including left and right laterallyspaced-apart sides LP,RP. The platform P′ is supported by and connectedto a chassis C including first (left) and second (right) spaced-apartbeams B1,B2 that extend parallel to each other and to the longitudinalaxis L from the forward end FT to the rear end RT. Each beam B1,B2defines an I-beam profile comprising an upper flange F1 and a lowerflange F2 (FIG. 2B) connected by a web BW. The beams are defined fromaluminum alloy (sometimes referred to herein simply as “aluminum”)extrusions, e.g., fabricated from first and second T-shaped extrusionsthat are arranged with their bases abutted and welded or otherwiseconnected together so as to define the illustrated I-beam profile. Theupper flanges F1 can extend horizontal or flat (i.e., in a horizontalplane) between the forward and rear trailer ends FT,RT or, as shown inFIGS. 3A and 3B, are preferably arched between the forward and reartrailer ends FT,RT, so that at least the upper flange F1 of each beamB1,B2 follows a convex arch with the apex of the arch oriented upwardtoward the platform P′ between the forward and rear trailer ends FT,RT.

A kingpin K is located at the forward end FT of the trailer T′,centrally located between and connected to the beams B1,B2, and isadapted to be engaged by a fifth-wheel of an associated tractor/truckfor towing the trailer T′. The rear end RT of the trailer includes atleast one and typically at least two axle assemblies A connected to thechassis C, e.g., to the lower flanges F2 of beams B1,B2. Each axleassembly A comprises at least one left and at least one right rotatablewheel and tire assembly W for movably supporting the trailer T′ on aroad or other surface. The trailer T′ further comprises a dolly assemblyD, typically located axially between the kingpin K and an axial midpointof the trailer T′. The dolly assembly D includes support feet DF thatare selectively lowered to support the forward end FT of the trailer T′when the kingpin K is not connected to an associated tractor/truck (thedolly assembly D is omitted from the background of FIG. 4B for clarity).

The platform P′ comprises left and right side rails RL′,RR′ that delimitthe opposite lateral sides LP,RP of the platform, respectively. Theseside rails RL′,RR′ are each typically defined as one-piece or monolithicextrusions of aluminum having a profile such as that shown in FIG. 4Band that extend in one piece from the forward end FT to the rear end RTof the trailer T. The side rails RL′,RR′ lie in respective verticalplanes that are parallel to the webs BW of beams B1,B2 and parallel tothe longitudinal axis L (the profiles of the side rails RL′,RR′ aretypically mirror images of each other as shown herein). If the beamflanges F1 are arched, the side rails RL′,RR′ are correspondinglyarched. The side rails RL′,RR′ include lower flanges RF for slidablymounting a winch or clip for securing a cargo-retaining strap, andinclude mounting slots CP for securing chain plates.

The platform P′ is further defined by a plurality of one-piece extrudedhollow cross member floor panels XP each arranged transverse, preferablyperpendicular, relative to the longitudinal axis L. Each panel XP isconnected to and extends in an uninterrupted fashion from the left siderail RL′ to the right side rail RR′ and preferably meets the railsRL′,RR′ at a right angle. As shown in FIG. 4A, the platform P′comprises: (i) a left section PL defined between the left side rail RL′and the lateral center of the beam B1; (ii) a middle section PM definedbetween the lateral centers of beams B1,B2; and, (iii) and a rightsection PR defined between the lateral center of beam B2 and the rightside rail RR′. Because each extruded panel XP extends to and entirelybetween the left and right side rails RL′,RR′ in one-piece, the left,middle and right platform sections PL,PM,PR are each partially definedby every extruded panel XP of the platform P′.

As shown in FIG. 4A, each panel XP includes first (front) and second(rear) edges or sides E1,E2, and longitudinally adjacent panels XP areabutted with the first edge of a panel XP abutted with the second edgeE2 of the adjacent panel, so that laterally extending seams S aredefined and extend to and between the left and right side rails RL′,RR′.As such, due to the shape of the panels XP as described in furtherdetail below, the platform P′ comprises and upper or top(cargo-supporting) surface P1′ that is smooth and uninterrupted exceptfor the seams S, and also comprises a lower or bottom surface P2′ thatis likewise smooth and uninterrupted except for the seams S so as toreduce wind drag and to prevent undesired accumulation of ice, mud orother debris. The adjacent abutted panels XP are preferably fixedlysecured to each other at the seams S by welding, adhesive, snap-fit,friction fit, or otherwise. If welded, it is preferred that the weld(s)extend along the seam S uninterrupted at least from the left side railRL′ to the right side rail RR′. Most preferably each weld extendsuninterrupted from and between the left and right lateral ends DL,DR(FIG. 4B) of each panel XP so that at least part of the weld of the seamS is received into the floor receiving channels NL,NR of the left andright side rails RL′,RR′. As shown in FIG. 4C, each seam S can be weldedwith an upper weld WU located adjacent the platform upper surface P1′and/or with a lower weld WL located adjacent the platform lower surfaceP2′. Preferably, the panels XP are interconnected so as to define theplatform P′ to have an arch to conform with an arch defined by the upperflanges F1 of beams B1,B2.

FIG. 4C is a sectional view of the platform P′ as taken at line C-C ofFIG. 4B, and shows first and second extruded floor panels XP (i.e.,first panel XP1 and second panel XP2) of the platform P′. The smooth anduninterrupted upper and lower platform surfaces P1′,P2′ are readilyapparent in FIG. 4C, as is the seam S defined where the panels XP1,XP2are abutted at their respective edges E1,E2.

With reference also to FIG. 5, the profile of an individual panel XPformed in accordance with the present invention is shown. The panel XPis preferably defined as a monolithic member, most preferably as anextrusion of aluminum, i.e., an aluminum alloy such as 6061-T6 aluminumalloy or another suitable aluminum alloy, having the illustratedprofile. The panel XP comprises an upper wall 12 a with a smooth planaror other flat outer surface 12 as oriented upward to define, togetherwith the other panels XP of platform P′, the cargo-supporting uppersurface P1′ of the platform P′. The panel XP further comprises a lowerwall 12 b with a smooth planar or other flat outer surface 12 bsoriented downward to define, together with the other panels XP, thelower surface P2′ of the platform P′. As used herein, a “flat surface”is intended encompass a perfectly smooth, planar surface and also a flatsurface having a surface texture defined therein by ribs, grooves or thelike that do not change the overall orientation or direction of thesurface, e.g., grooves having a depth less than or ribs having a heightless than the thickness of the walls 12 a,12 b. The upper and lowerouter surfaces 12 as,12 bs lie in respective horizontal planes and arearranged in parallel spaced-apart relation to each other. The upper andlower walls 12 a,12 b can have the same minimum thickness but, becausethe upper wall 12 a is in contact with the cargo while the lower wall 12b is not, it is preferred that the upper wall 12 a have a minimumthickness T₁ that is greater than the minimum thickness T₂ of lower wall72 b to reduce weight and material cost while providing the requiredstrength where needed.

With reference again to FIGS. 4C and 5, in an alternative embodiment,the extruded panel XP1 has a larger minimum wall thicknesses T₁ for itsupper wall 12 a as compared to the panel XP2, so that the platformsection constructed with the thicker panels XP1 has a stronger uppersurface P1′. This alternative structure allows for selective sections ofthe trailer platform P′ to be constructed with the stronger panels XP1(e.g., a steel coil cargo carrying region or a rear region where a lifttruck moves onto and off of the platform P′) for added strength andallows other lower-stress sections of the trailer platform P′ to beconstructed with the lighter-weight panels XP2.

The upper and lower walls 12 a,12 b are joined by opposite first andsecond end walls 12 c,12 d which, in the illustrated embodiment, arearranged in parallel spaced-apart relation to each other in respectivevertical planes. The end walls 12 c,12 d comprise respective matingconformations such as the illustrated male rib 12 r and female groove 12g. As shown in FIG. 4C, the rib 12 r and groove 12 g are sized for closesliding receipt of the rib 12 r of a first panel XP1 into the groove 12g of a second panel XP2 abutted with the first panel so that a pluralityof the panels XP define the platform P′. This mechanical connection ofthe panels XP1,XP2 increases strength and facilitates a subsequentbonding operation by suitable means such as the preferred weldingoperation or, alternatively, adhesive and/or fasteners for permanentlysecuring the panels to each other to define the platform P′. Moreparticularly, as is also apparent in FIG. 4C, the panels XP1,XP2 aredefined so that when they are abutted to define a platform P′, theabutted panels cooperate to define first and second welding groovesV1,V2 adapted to receive the welds WU,WL, i.e., each panel XP1,XP2defines half of each groove V1,V2. Alternatively, the grooves V1,V2 canreceive an adhesive used to permanently affix the panels XP1,XP2 to eachother.

Referring again specifically to FIG. 5, each panel XP defines at leastone support wall in its profile, such as the illustrated primary I-beamcross-member 14. The one or more primary I-beam cross-members 14 arepreferably equally spaced or distributed between the end walls 12 c,12d. The primary I-beam cross-member 14 (only one illustrated in FIG. 5)comprises a support web 14 a that spans the space between walls 12 a,12b and first and second flanges 14 b,14 c arranged transversely relativeto the support web 14 a. Preferably the web 14 a lies in a verticalplane and the flanges 14 b,14 c are perpendicularly connected to the web14 a. The flanges 14 b and 14 c have respective symmetrical first andsecond halves 14 b 1,14 b 2 and 14 c 1,14 c 2. The flange halves 14 b1,14 b 2 each define a thickness T₃ and the flange halves 14 c 1,14 c 2each define a thickness T₄.

In the illustrated embodiment, the thicknesses T₃,T₄ of the flanges aremaximized and are greater than the respective wall thicknesses T1,T2adjacent support web 14 a, and taper as the distance from the supportweb 14 a increases, until the thickness T₃,T₄ is equal the minimumthicknesses T₁,T₂ of walls 12 a,12 b, respectively. For added strength,the maximum thickness T₃ of flange 14 b is preferably greater than themaximum thickness T₄ for flange 74 c to provide added strength to upper(cargo carrying) wall 12 a and to reduce weight/material for lower wall12 b. Each panel XP thus defines at least two horizontally-extendinghollow cores 15 separated from each other by a primary I-beamcross-member 14. Although the I-beam cross-member 14 is shown withtapered flanges 14 b,14 c, the flanges 14 b,14 c can alternatively haverespectively constant thicknesses, e.g., the wall thicknesses T1,T2,respectively.

In addition to the primary I-beam cross-member(s) 14, each panel XPfurther defines first and second partial or half I-beam cross-members 18a,18 b that are preferably mirror-images of each other. Moreparticularly, the first half I-beam cross-member 18 a comprises a webdefined by the end wall 12 c, and first and second half-flanges 18 a1,18 a 2 that are connected to and project transversely from the endwall 12 c. The half-flanges 18 a 1,18 a 2 have respective thicknessesT₅,T₆ that are preferably but not necessarily maximized and greater thanthe respective wail thicknesses T₁,T₂ adjacent end wall 12 c and thattaper as the distance from end wall 12 c increases until the thicknessesare equal to the minimum wall thickness T₁,T₂, respectively.

Similarly, the second half I-beam cross-member 18 b comprises a webdefined by the end wall 12 d, and first and second half-flanges 18 b1,18 b 2 that are connected to and project transversely from the endwall 12 d. The half-flanges 18 b 1,18 b 2 have respective thicknessesT₇,T₈ that are preferably but not necessarily maximized and greater thanthe respective wall thicknesses T₇,T₈ adjacent end wall 12 d and thattaper as the distance from end wall 12 d increases until the thicknessare equal to the minimum wall thicknesses T₁,T₂, respectively.

Referring again to FIG. 4C, those of ordinary skill in the art willrecognize that when the first and second floor panels XP1,XP2 areabutted, with the rib 12 r seated in groove 12 g and walls 12 c,12 d incontact or very closely adjacent, and when the grooves V1,V2 are filledwith a welding bead or adhesive, the first half I-beam cross-member 18 aof the first panel XP1 and second half I-beam cross-member 18 b of thesecond panel XP2 together define a full secondary I-beam cross-member114 that has a structure that is at least substantially identical to theone or more primary I-beam cross-members 14. As such, platform P′defined from a plurality of interconnected panels XP will comprise atleast one primary I-beam cross-member 14 defined as part of each panelXP, and another secondary I-beam cross-member 114 defined at the seam Sbetween each pair of abutted panels XP. As such, the platform P′includes integral cross-members comprising the primary I-beamcross-member 14 of each panel XP and the secondary I-beam cross-members114 defined by each pair of abutted interconnected panels XP.Accordingly, the platform P′ need not comprise separate transversecross-members such as the cross-members CM described above in relationto the trailer T. Instead, as shown in FIG. 4B, the platform P′ isself-supporting on the beams B1,B2 so that the lower surface P2′ of theplatform P′ is more aerodynamically efficient owing to the absence ofexternal cross-members.

FIG. 6 illustrates an alternative floor panel XP′ that is identical tothe panel XP except as otherwise shown and/or described. The floor panelXP′ can be used in place of all or some of the floor panels XP used todefine the platform P′. For example, the panels XP′ are used where ahigher-strength platform P′ or section thereof is required, e.g., asteel-coil cargo carrying section or a region expected to receiverepetitive lift truck travel or other extreme forces. The panel XP′comprises in its extrusion profile as shown including at least twointegral I-beam cross-members 14′ instead of a single I-beamcross-member. As such, at least three hollow core regions 15′ aredefined, but each hollow core region 15′ has a width that is smallerthan a corresponding width of the hollow regions 15 of floor panel XP toincrease the strength of the panel XP′ relative to the panel XP. Ofcourse, the panel XP′ can include four or more voids 15′ if additionalcross-members 14′ are included for even more strength.

Referring again to FIG. 4B, the left and right side rails RL′,RR′,comprise respective inwardly directed floor receiving channels NL,NRthat receive and retain the opposite left and right ends DL,DR of eachpanel XP between upper and lower horizontal channel walls N1,N2. Thefloor-receiving channels NL,NR also include an inner vertical channelwall N3 that extends between and interconnects the upper and lowerhorizontal channel walls N1,N2 so that the floor-receiving channels areC-shaped in cross-section in the illustrated embodiment. As part of theextrusion profile or otherwise, the left and right side rails RL′,RR′each comprise a stand-off nib F that prevents the panel edges DL,DR fromcontacting the inner channel wall N3. As such, any water that enters thecore 15,15′ of a panel XP,XP′ through a puncture can flow laterallyoutward into the floor-receiving channels NL,NR for drainage from thetrailer T′. Preferably, the upper and/or lower channel walls N1,N2 arewelded or otherwise fixedly secured to the upper and lower platformsurfaces P1′,P2′ for added strength and so that the side rails RL′,RR′can be used as anchor locations for cargo hold-down systems.

The platform P′ is connected to the beams B1,B2 by any suitable means.As shown, welds WP are used to secure the underside P2′ of platform P′to the upper flanges F1 of the beams B1,B2. For each beam B1,B2, firstand second welds WP are located at first and second (left and right)interfaces of the beam upper flange F1 with the lower surface P2′ of theplatform P′. Each weld WP preferably extends continuously anduninterrupted along the interface between the beam B1,B2 and theplatform underside P2′ for the axial length of each beam. Additionallyor alternatively, fasteners M such as bolts, U-bolts or the like arepassed completely or partially through the platform P′ and secured tothe upper flanges F1 of the beams B1,B2 as shown in broken lines. Also,struts or braces or “outriggers” T can optionally be used to connect theleft side rail RL′ (or the underside P2′ of the left platform sectionPL) to the beam B1 and to connect the right side rail RR′ (or theunderside P2′ of the right platform section PR) to the beam B2, whichfurther fixedly secures the platform P′ to the beams B1,B2. In suchcase, the struts T are welded in position and/or are connected usingfasteners.

The platform P′ is preferably arched to conform with an arch of at leastthe upper flanges F1 of the beams B1,B2 as shown in FIGS. 3A and 3B.Various structures and methods can be used to provide a platform P′ thatis arched to conform to the arch of the beams B1,B2. In one embodiment,it is contemplated that the platform P′ comprise separate sections offloor panels XP, wherein each section comprises a single panel XP or twoor more interconnected panels XP as shown in FIG. 4C, but wherein theseparate floor sections or one or multiple interconnected panels are notconnected to each other to allow the platform P′ to have a non-planar,e.g., arched, configuration that follows the arch of the beams B1,B2. Inanother embodiment as shown in FIG. 7, the panels XP (shown onlydiagrammatically) are welded together at the seams to define a platformsubassembly PA′ with a built-in arch that corresponds to the arch of thebeam B1,B2. The side rails RL′,RR′ are then fitted and welded to theplatform subassembly PA′ to define a platform P′, and the platform P′ isthen fitted to the upper flanges F1 of the beams B1,B2 and welded orotherwise secured to the beams as described above.

Referring to FIGS. 8A and 8B, another embodiment is diagrammaticallyillustrated. In such embodiment, a platform subassembly PA″ (which ispreferably the entire length of the platform P′, but can be only part ofthe platform length) is constructed by welding together a plurality ofpanels XP at the seams S as shown in FIG. 4C. The platform subassemblyPA″ is flat or otherwise shaped without an arched configuration thatcorresponds to the arch of the beams B1,B2. The platform subassembly PA″is preferably inverted and supported on a support surface SS which canbe flat or, as shown, can include a concave form CC shaped to correspondwith the desired arched shape for the finishes platform P′. The beamsB1,B2 (only beams B1 is visible) are inverted and then engaged with theplatform subassembly PA″ and are used to urge the platform subassemblyPA″ against the support surface SS with a force F1 so that the platformsubassembly PA″ deforms and conforms to the arched configuration of theupper flanges F1 of the beams B1,B2 (the force F1 is preferably appliedto both beams B1,B2 simultaneously). It is most preferred that the beamsB1,B2 be welded to the platform subassembly PA″ along the full axiallength of the upper flanges F1 of both beams B1,B2 via welds WP at theinterface of the beam upper flanges F1 with the platform subassembly PA″while the force F1 is continuously applied, to provide a prestressedwelded structure including the beams B1,B2 and the platform subassemblyPA″. The platform subassembly PA″ is preferably provided as a completeplatform P′, i.e., the platform subassembly includes the side railsRL′,RR′, or the side rails RL′,RR′ can be applied after the platformsubassembly PA″ is connected to both beams B1,B2. The resultingprestressed, welded structural unit including the beams B1,B2 andplatform P′ is resistant to sagging when loaded which provides astructural and an aesthetic benefit. The arch of the platform P′ isdefined herein as having a longitudinal axis that is perpendicular tothe longitudinal axis L of the trailer T′, such that each panel XPextends parallel to the longitudinal axis of the arch.

FIGS. 9 and 10 illustrate alternative profiles for the beams B1,B2. FIG.9 shows a first alternative beam profile B1′,B2′ in which the upper andlower flanges F1′,F2′ are shaped differently from each other, with theupper flange F1′ defining a lateral width LW1 and a thickness FT1smaller than a corresponding lateral width LW2 and thickness FT2 of thelower flange F2′. The beam B1″,B2″ of FIG. 10 is similar, but the lowerflange F2″ is asymmetric in the sense that a fillet FL is definedbetween the web BW and flange F2″ on a first lateral side of the web,while the opposite lateral side of the web BW joins the flange F2″ witha non-filleted connection FL′. This structure is believed to providesuperior strength and durability by eliminating stress concentrations.

The present invention has been described with reference to preferredembodiments. It is not intended that the invention be limited to thepreferred embodiments, and this specification is intended to beconstrued literally and/or according to the doctrine or equivalents toencompass modifications and alterations to the fullest possible extent.

1-18. (canceled)
 19. A method for constructing a platform trailer, saidmethod comprising: constructing a platform subassembly comprisingplurality of extruded aluminum panels that each extend from a leftlateral end to a right lateral end, wherein said extruded aluminumpanels are abutted in series to define a cargo supporting surface ofsaid platform subassembly; exerting a force on said platform subassemblyto form an arch in said platform subassembly; while said force isapplied to maintain said arch in said platform subassembly, weldingfirst and second parallel, spaced apart arched beams to said platformsubassembly; removing said force from said platform subassembly aftersaid first and second arched beams are welded to said platformsubassembly.
 20. The method for constructing a platform trailer as setforth in claim 19, wherein said arch is defined about a longitudinalaxis that is perpendicular to a longitudinal axis of said first andsecond beams, wherein each of said panels extends parallel to saidlongitudinal axis of said arch.
 21. The method for constructing aplatform trailer as set forth in claim 19, further comprising connectingleft and right aluminum side rails to opposite left and right lateralsides of said platform subassembly, respectively, wherein each of saidpanels extends between said left and right side rails.
 22. The methodfor constructing a platform trailer as set forth in claim 19, whereinthe cargo supporting surface of said platform subassembly is orienteddownward when said force is applied.
 23. A method for constructing aplatform trailer, said method comprising: constructing a platformsubassembly comprising plurality of extruded aluminum panels that eachextend from a left lateral end to a right lateral end, each of saidpanels comprising an upper wall, a lower wall spaced-apart from saidupper wall, and first and second spaced-apart end walls that areconnected to and extend between the upper and lower walls, wherein saidextruded aluminum panels are abutted in series with the first end wallof one panel abutted with the second end wall of an adjacent abuttedpanel such that the respective upper walls of adjacent abutted panelsdefine a cargo supporting surface of said platform subassembly; and,welding first and second parallel, spaced apart arched beams to saidplatform subassembly.
 24. The method as set forth in claim 23, whereinsaid constructing step comprises welding said adjacent abutted panels toeach other such that said platform subassembly defines a built-in arch.25. The method for constructing a platform trailer as set forth in claim19, wherein each of said panels comprises an upper wall, a lower wallspaced-apart from said upper wall, and first and second spaced-apart endwalls that are connected to and extend between the upper and lowerwalls.
 26. A method for constructing a platform trailer, said methodcomprising: constructing a platform subassembly comprising a pluralityof extruded aluminum panels that each extend from a left lateral end toa right lateral end; connecting first and second parallel, spaced apartbeams to said platform subassembly in a manner such that a cargosupporting surface of the platform subassembly defines an arch; and,connecting at least one axle assembly to said first and second spacedapart beams, said at least one axle assembly including at least one leftwheel and tire assembly and at least one right wheel and tire assembly.27. The method of claim 26, further comprising: connecting a left siderail adjacent the left lateral end of the extruded panels; and,connecting a right side rail adjacent the right lateral end of theextruded panels.
 28. The method of claim 26, further comprising: formingsaid arch in said platform subassembly before said first and secondbeams are connected to said platform subassembly.